#7854
add a new task which take the delau as optional argument (default to 3). When fired the task scan all tickets for sleeping or orphaned ones. Sleeping tickets are assigned tickets that don't have any changes since more than the specified delay. Orphaned tickets are new ticket and non assigned.

While doing message markup some msgid changes where incorporated as well.
Initial message extraction has been done and German translations added.
There is still more work required, i.e. to send localized email messages.

This is a follow-up to changeset [9277] as we introduce an easy way to
enable/disable this feature while keeping the new default behavior
of making email address verification mandatory on activation of
EmailVerificationModule.
I've taken the chance for some cosmetic changes as well, especially to
remove radio buttons and use checkboxes consistently for all options.